4results about How to "Avoid Longitudinal Cracks" patented technology

The utility model relates to a connecting tool for partial prestress electric pole production, which comprises a tensioning disc connected with a plurality of steel bars, and further comprises a connecting nut connected on the tensioning disc through a fixing bolt, the connecting nut is pre-buried in concrete, the connecting nut extends to the inner end face of the tensioning disc, and the steel bars are arranged on the tensioning disc. The end of the steel bar is installed in the connecting nut, the connecting nut comprises a shell, a threaded hole is formed in the shell, the fixing bolt is in threaded connection in the threaded hole, a pier head groove is formed in the shell, the end of the steel bar is installed in the pier head groove, the steel bar comprises a bar body, and pier heads are connected to the two ends of the bar body. According to the prestressed steel bar tensioning device, the steel bar and the tensioning disc are connected through the connecting nut, the prestressed steel bar does not need to be cut off and released after demolding, and only the bolt needs to be detached.

The present invention proposes a beam bridge without a central partition, without a hanging formwork, and without a negative bending moment tooth block, and a design method thereof. The beam bridge includes a prefabricated main beam, a wet joint, a lower structure, and a pier top crossbeam above the lower structure. The concrete bridge decks of adjacent prefabricated main beams are connected by a wet joint. The design method of the above beam bridge includes the following steps: S1, initial design of the main beam; S2, calculation of the non-uniform deflection of the main beam and the indirect transverse stress of the bridge deck; S3, calculation of the direct transverse stress of the bridge deck; S4, crack resistance verification of the bridge deck; S5, optimization of bridge parameters to reduce the stress on the driving surface; S6, completion of the beam bridge design. The beam bridge and its design method effectively solve the problem that the existing beam bridge without a central partition is prone to longitudinal cracking at the joints, and realizes the suspension tension without the wet joint hanging formwork of the bridge deck and the negative bending moment beam, and has better mechanical properties and better economic, environmental and social benefits, which can facilitate the promotion and application of such bridges in various types of highways, railways and municipal engineering.

This invention discloses a CRTS-Ⅲ type ballastless track, relating to the field of track technology, comprising a base plate, a track slab, and a filling layer; the filling layer is formed by pouring self-compacting concrete between the track slab and the base plate; a corrugated steel frame is embedded within the track slab; the corrugated steel frame is assembled from a main corrugated plate, perforated channel steel, and strip corrugated plates. The CRTS-Ⅲ type ballastless track provided by this invention can avoid interlayer cracking and track slab cracking in slab ballastless tracks.

The utility model relates to a permafrost roadbed cooling structure for reducing differential settlement of a road surface. The permafrost roadbed cooling structure comprises a block stone extrusion layer arranged in a natural foundation, an embankment arranged on the block stone extrusion layer, ventilation bricks arranged on the embankment, a plurality of L-shaped hot rods, a U-shaped drainage ditch and a water seepage blind ditch. The natural foundation is a permafrost region road foundation; a transverse drainage slope is arranged at the bottom of the block stone extrusion layer, and waterproof geotechnical cloth I and a water guide pipe are laid on the transverse drainage slope; the embankment is formed by paving a cushion layer, filling soil and an asphalt pavement from bottom to top in sequence; waterproof geotextile III and permeable geotextile are laid on the cushion layer; waterproof geotechnical cloth II is laid on the slope surface of the filled soil; a reinforced grating and an insulation board are laid in the filling soil; the plurality of L-shaped hot rods are inserted into slope toes on two sides of the embankment; a U-shaped drainage ditch and a water seepage blind ditch are arranged on each of the two sides of the roadbed. According to the utility model, the problem of permafrost degradation below due to heat absorption of the roadbed in a permafrost region and the problem of longitudinal cracking of the pavement due to non-uniform deformation of the roadbed are effectively solved.